A testimonial, from the pages of Galileo's Daughter:

By his own reckoning [...], his conclusions on resistance and motion outwieghed all the astronomical discoveries that immortalized his name. Surely Galileo prided himself on having been the one to build a proper telescope and point it toward the sky. But he believed his own grteater genius lay in his ability to observe the world at hand, to understand the behavior of its parts, and to describe these in terms of mathematical proportions.

Posterity completely agrees with Galileo in this assessment of is merits. As Albert Einstein noted, "Propositions arrived at purely by logical means are completely empty as regards reality. Because Galileo saw this, and particularly because he drummed it into the scientific world, he is the father of modern physics - indeed of modern science altogether."

[Sobel, Dava; Galileo's Daughter; 1999, NY, Walker & Co.; p. 326 - the second paragraph is a footnote at the bottom of that page]